Automatic burglar and fire alarm



1937; I F. R. DAVIDSON 2,090,574

AUTOMATIC BURGLAR AND FIRE ALARM Filed Oct. 25, 1935 60 8- [1 b L I :1

671 H 24 I l l 5 Sheets-Sheet 1 Aug. 17, '1937. F, DAWDSON 2,090,574

AUTOMATIC? BURGLAR AND FIRE ALARM Filed Oct. 25,1955 5 Sheets-Sheet 2 Patented Aug. 17, 1937 PATENT {OFFICE 2,090,574 AUTOMATIC BURGLAR AND rum ALARM Francis Rupert Davidson, Southend-on-Sea, England i Application October 23, 1935, Serial No. 46,408

V In Great Britain October 23, 1934 11 Claims.

This invention relates to automatic burglar and fire alarms, and has reference to alarm devicesof the type comprising a gramophone or like sound reproducing device operatively connected with a telephone line and associated with means automatically to establish communication with a fire, police or other station and to trans mit a suitable message to said station upon the occurrence of a burglary or fire. In this type of apparatus an electromagnet is employed which,

upon the unauthorized opening of a door, window, safe or the like or upon a sudden rise in temperature, operates to release trip mechanism to start the gramophone motor to operate a dialing device and thereby establish communication with the desired station.

In this type of apparatus it has also been proposed normally to isolate the alarm device from the telephone system, communication being es- 2O tablished automatically when the device is set into operation by the unauthorized opening of a door or the like, means also being provided whereby the message can be repeated if desired.

According to the present-invention-the alarm device comprises in combination a gramophone or like sound reproducing device operatively connected with a telephone line in association with means automatically to establish communication with a fire, police or other station upon the op- 30 currence of a fire or burglary and to transmit a suitable message to said station, in which the gramophone motor is started by trip mechanism released by an electromagnet, the trip mechanism for starting the motor also operating simul- 35 taneously to connect the transmitter of the alarm device with the telephone system to open the line, and whereinthe gramophone motor operatesv mechanism which successively dials the emergency dialing symbol, lowers the sound box or 40 pick-up on to the sound reproducing record to produce the message or alarm to be transmitted returns the souiifd box or pick up to the commencement of the record to repeat the message or alarr'ri, then clears the line and finally dis- 45 connects the transmitter from the telephone system.

In one particular form of the invention an ordinary telephone instrument is employed as the transmitter, said instrument being normally iso- 50 lated from the telephone system but connected therewith. simultaneously with the starting up of the gramophone motor, this being effected by weight actuated lever mechanism which upon being released by the electromagnet lifts the 55 receiver arm of the telephone instrument simultaneously to close two contacts to connect the instrument with the telephone system, and make the line.

If desired means may gramophone motor. y

In order that the invention may be more clearly understood one particular construction thereof will now be described, by way of example with reference to the accompanying drawings wherein:

Figure 1 is a side elevation of the trip mechanism for starting the motor, connecting the telephone instrument with the telephone system, and opening the line.

Figure 2 is a plan view of the apparatus.

Figures 3 and 4 are respectively a plan and side view '(from arrow vanism, and

Figures 5 and 6 are side elevations of parts of the mechanism shown in the upper part of Figure 2.

Referring to these drawings the apparatus comprises a gramophone motor '2 and a turntable III) of the dialing mechbe provided to stop the 2a; a telephone instrument 3; weight actuated lever mechanism (Figure trip mechanism operated by an electromagnet i for starting the gramophone motor, lifting the receiver arm l1 and putting the normally isolated telephone instrument into circuit with the tele-' phone system; link and lever mechanism operated by a rack 28 driven by the motor 2 to dial 0" (or other emergency symbol) and lower the gramophone sound box 'onto the sound record; lever mechanism operated by a second rack 50,

also driven by the motor 2, for returning the sound box 12a to the commencement of the sound 1 record to repeat the message or alarm; and cam and weight actuated lever mechanism 82, 13-15 for finally replacing the receiver arm disconnecting (and thus isolating) the telephone instrument 3' from the telephone system. The complete apparatus is preferably enclosed in a sound proof casing.

Referring to the trated in Figure 1, the

starting mechanism illusopening of a door, window, safe or the like and releases a catch 5 which forms part of a lever 6 pivoted at l to one of two vertical supports 8 mounted on a box plate 9. Said lever 6 is coupled by a pivoted link III to a rocking lever H itself pivoted at l2 to the cross arm supports 8,- and provided at its outer free end with a weight leased in the manner described above, causes said rocking lever H to fall into the position shown 1) set into motion by v electro-magnet 4 is en-' ergized for example, upon the unauthorized- I3 of the I M which, when the catch 5 is rethe upper edge of the lever ii, so that as the. lever Ii moves downwards the latch drops,

under its own weight, out of engagement with the 10 stop 2b on the turntable. I

Simultaneously with the starting of the motor 2 the receiver arm I1 of the telephone instrument 3 is lifted. This operation is also effected by thev rocking-lever H, the downward movement 16 of which releases a catch i6 which normally holds the receiver arm l1 in its depressed position.

The catch I6 is pivoted at 26 and pivotallyconnected to a link 2| provided with a longitudinal slot into which projects a pin 22 on the lever I I. 20 thus when thelever l I falls said pin 22 moves the link downward whereby the catch I6 is turned about its pivot 26 and caused to disengage the receiver arm l1 which is thus free to lift.

Connected to the receiver arm l1 at its upper end is a flat rod 23 the lower end of which is connected to a crank 24 which is mounted in bearing 25 and carries an eccentric cam 26. When the receiver arm l1 lifts the rod 23 connected to it operates the crank to rotate the cam 26 whereby contacts 21, 21a are closed to make the .circuit between the normally isolated telephone instrument and the telephone system. The lever mechanism 13-15 and the weight controlled lever 66 shown in Figure 1 operate respectively to return the receiver arm I1 to its depressed position and to break the telephone clrcult after the alarm message has been transmitted the desired number of times, and will be described more-fully hereinafter.

.40 In Figure 2 the mechanism for effecting the 'various subsequent operations is shown in its 1 initial position. Referring to this figure a rack 26 is mounted in guides 29 on one side of the motor 2 and is normally in mesh with a toothed member of said motor, preferably the lower toothed annulus which through step-up gearing drlves'the spindle of the turn-table. When the motor 2 starts, the rack 26 is driven in its guides 29 in the direction ofthe arrow and by the intermediary of a two armed lever 36 drives a rack 33 in the opposite direction to drive the dialing member hereinafter described. The two armed lever 39 is pivoted to a support, 3|, and one arm of said lever projects through a vertical slot formed in the rack 26 while the other arm is connected 'to the rack 33 by a link 32 forming an articulated joint.

The dialing mechanism, illustrated in Figures 3 and 4, is mounted on a bracket 62 and consists of a. rotary shaft 63 on the upper end of which is mounted a pinion 64 which engages with the rack 33 slidable in a guide member 33a. On the lower end of said shaft 63 is rigidly secured a .radial arm 65 which carries at its free end a 05 sleeve 66 in which is slidably arranged a pin 61' adapted to engage in any selected aperture in the dialing disc 66 of the telephone. Projecting radially from'the pin 61 is a finger 69 which, as. hereinafter described, is caused to ride over 70 the upper cam surface of the sleeve 66 to withdraw the pin 61 from the aperture in the'dialing disc 66, after said disc has been rotated in clockwise direction. In operation the rack 33, driven in'the manner described above, drives the .75 pinion 64' and thus rotates the shaft 63 whereby the pin 61 is moved in an arcuate path in a clockwise directionand, since it is arranged in one of the apertures of the dialing disc 66, rotates said disc to commence the dialing operation. Just'before the pin 61 reaches the stop 10 during the dialing operation the finger 69, projecting radially therefrom abuts againsta projection 1| on the bracket 62, so that as the pin completes the clockwise rotation of the disc 66, it is itself caused to rotate' in the sleeve 66, whereby the finger 69 rides over the cam surface of said'sleeve 66 and lifts the pin 61 out of engagement with the disc 66, thereby releasing said disc so that it can rotate in an anti-clockwise direction in the usual manner to complete the dialing operation and establish communication with the desired station.

In addition to the dialing operation the rack 26 also operates to lower the sound box of the gramophone onto the sound record. The arm 12 carrying-the sound box is supported in a recessed cross-piece 33b of an arm 4i, one end of which is pivoted at 34 to a support 36 and the other and rests on a cam 36 (see-Figure 5) rigidly mounted on a rotary shaft 31 mounted in a sleeve formed on the support 35. To the opposite end of the shaft 31'is' rigidly secured a collar 36 to which is fixed one end of a crank 39 the otherend of which projects'between pins 46 of the rack 26. The normal position of the cam 36 is such that the sound box 12a on the arm 12, is

suspended above the commencement of the sound record as shown in Figure 5. As soon as the rack 26 begins to move, as described above, the movement is'transmitted to the crank 39 which in turn rotates the shaft 31 and with it the cam 36 whereby the arm H, which supports the arm 12 carrying the sound box, is lowered and thereby gently lowers the sound box 12a onto the sound record, whereupon the acoustic output of the gramophone is picked up by the telephone transmitter.

When the rack 26 has travelled a suflicient distance to complete the dialing operation and lower out of engagement with the motor by the guides 29 until it has travelled a given distance, (i. e.

the distance necessary to complete the various operations which it is intended to perform) when a notch 46 formed in the rack reaches the first guide 29 whereupon said rack snaps out of engagement with the motor.

As the sound box travels over the record it con-.

tacts with'a lever 41 mounted on a vertical shaft 46 which is thus rotated and rotates with it a cam '49 which is mounted on the lower end of said shaft and against which one end of a spring loaded lever 52 is pressed. The said lever 52 is pivoted at 53 and is provided on its upper surface with guides i for a second rack 50. At the moment when the sound box reaches the end of its 5 travel over the sound record the cam 49 will have been rotated so far by the movement of the lever 41 that the pivoted lever 52 will, under the action shaft 56. To the upper end of .this shaft 56'is l5 rigidly secured a lever 51 which is in turn connected, by means of an articulated link 59, to a lever 58 which is itself pivoted at its lower end to a support 60 and provided at its upper end with an outwardly projecting pin 6|. When the rack 50 is driven-in the direction'of the arrow,- the movement thereby imparted to the levers 55, 51 is transmitted through the link 59 and causes the lever 58 to rotate in a vertical plane about its pivot, thus the pin BI is moved 'in'an arc, as shown in Figure 6. The initial position of the lever 58 is such that the pin 6| is located immediately below the supporting arm 12 of the soundbox at the moment when said sound box has reached the end of the record (position B Figure 6), thus when the sound box reaches this position and the pin 6|, is moved in the manner described, said sound box will be lifted off the record by said pin 8 l, and

' carried to its initial position (position A Figure 6) at the commencement of the record to repeat 3 the message.

In-order to preventthemotor from continuing to drive the rack 58 after the above operations have been performed, a suitable number of teeth are cut away, so that said rack moves out of en- 40 gagement with the motor at the moment when the rack-has reached its end position.

After the record has been repeated a given number of times, in the present example twice,

spring controlled lever mechanism 13, 14, 15 is operated to release a weight actuated lever 16 to return the receiver arm l1 to its depressed position and clear the line, and to operate the cam 26 to break the contacts 21 and thus isolate the telephone instrument from the telephone system.

This mechanism is set into operation by the movement of the arm 12 carrying the sound box. On the arm 12 is pivotally mounted a pawl 11 which abuts against a pin 18 mounted on the upper surface of a plate 19 which is itself mounted at the upper end of a shaft 8ll rotatably mounted inasleeve 8|. The rotaryshaft 80 extends through the base plate 9 and is provided at its lower end below the-base plate 9, with a cam82. Pressed against this cam 82, by means of a spring 83, is

one end of a lever'13 which'is, pivoted at 84 and pivotally connectedat its opposite end to lever 14. In this lever 14 is a slot into which projects the lower end of a vertical lever 15 pivoted at 98 to the support 8 and provided at its upper end with a hook which engages with a pin 85 on the lower end of a rocking lever 86'pivoted at 81 to the support 8 and provided at its upper free end with 'a weight 88. In operation the arm 12 turns about its pivot as the sound record is being played and by means of the pawl 11 abutting against the pin 18moves said plate to rotate the shaft carrying the cam 82, which however is not rotated sufllciently to release the lever 18 until the record is played a second time. When the arm 12 is moved 75 back to its initial position, as'described above, to

return the sound box to the commencement sound record, the pawl 11 during the return movement of the arm 12, rides over and, is moved'behind a second pin 89 on the platej19 'so that as the sound box of the gramophone travels over. the

sound record a second time,'the cam 82 is rotated still further, and at the moment when the sound box has reached the end of the record the cam will have moved so far as to release the lever. 13, which underthe action of the spring 831" will'" thenswing about its pivot 84 and through the lever 14 will cause the vertical lever 15 to pivot and release its upper hooked end from the'p'i'n 85, whereupon the rocking lever 85 under the.

influence of its weight 88 will fall across the rod 89 and return the receiver arm |1 of the telephone to its depressed position. :Simultaneously with the depressing of the receiver arm l1 the contacts 21 will be broken as described above.

The contacts 21 are, as previously indicated,

closed upon operation of the cam 26 to connect,

thr telephone transmitter to the line. In order that the normal telephone system shall not be substantially aifected by the connection of the transmitter of the alarm device, it is preferable to make the connection in parallel. It is further desirable to arrange that the telephone transmitter has substantially the same characteristics as a normal telephone, and a speech transformer is therefore included in series with the transmitter in the usual manner, but the secondary winding of the transformer is. short circuited since there is no receiver to be connected. In this way the two connections to the telephone line are balanced. I I

It will be clearly understoodthat the alarm device according to the invention can be easily adapted for use as a fire alarm in which case the'electrical circuit controlling the trip mechanism would be established by a suitable thermostatlc device upon the occurrence of an ab normal rise in temperature;

I What I claim and desire to secure by Letters Patent is: 1. Alarm device comprising a gramophone and motor operatively-connected with a telephone line and operatively connected with means automatically to establish communication with an alarm receiving station upon actuation of the alarm and to transmit a suitable message to said station,

means for starting said gramophone motor com-' prising a trip mechanism, an electromagnet for releasing said trip mechanism, said trip mecha- 'nism having means operatively connected therewith-and operating simultaneously to connect the transmitter of the alarm device with the telephone system and to open the line, means 019- eratively connected with said gramophone motor for successlvey dialing the emergency dialing symbol, means for lowering thesound box onto the sound reproducing record to produce the alarm to be transmitted, means for returning the sound box to the commencement of the record to repeat the alarm, means for disconnecting the transmitter from the telephone system, and said trip mechanism comprising a pivotally mounted weight actuated lever which normally holds a latch in front of a stop on the gramophone turntable, link and lever mechanism connecting said lever with a catch which normally holds the receiver arm of a telephone transmitter in its de-' said rod being connected to a crank, said crank being adapted to rotate a cam to close the contacts when the receiver arm is released whereby the telephoneinstrument is connected in circuit with the telephone system.

3. The structure of claim 1, a rack and pinion mechanism operating said dialing mechanism, a second rack driven by the. gramophone motor, said second rack comprising means for actuating said rack and pinion mechanism.

4. The structure of claim 1, a rack and pinion mechanism operating said dialing mechanism, a second rackdriven by the gramophone motor, said second rack comprising means for actuating said rack and pinion mechanism, said second rack being coupled with said first rack by a twoarmed lever and .an articulated link whereby said second rack is driven in the opposite direction to said first rack.

5. The structure of claim 1,- a rack and pinion mechanism operating said dialing mechanism, a second rack driven by the gramophone motor, said second rack comprising means for actuating said rack and pinion mechanism, said second rack being coupled with said first rack by a two-armed lever and an articulated link whereby said second rack is driven in the opposite direction to said first rack, said dialing mechanism comprising a rotary shaft driven byssaid rack and pinion mechanism, said shaft having a radial arm carrying at its outer end a pin which projects into an aperture in the dialing disc.

6. The structure of claim 1, a rack and pinion mechanism operating said dialing mechanism, a second rack driven by the gramophone motor, said second rack comprising means for actuating said rack and pinion mechanism, said second rack being coupled with said first rack by a two-armedlever and an articulateddink whereby said second rack is driven in the opposite directionto said first rack, said dialing mechar'iism comprising a rotary shaft driven by said rack and pinion mechanism, said shaft having a radial arm carrying at its outer end a pin which projects into an aperture in the dialing disc,

' the dialing disc which is thereby released.

"l. The structure of claim 1, a rack and pinion mechanism operating said dialing mechanism, av

second rack driven by the gramophone motor, said second rackcomprlsing means for actuating said rack and pinion mechanism, said second to said first rack, and camand lever mechanism for lowering said sound box onto the sound record, said cam and lever mechanism being actuated by said second named rack. I v i 8. The structure of claim 1, a rack and pinion mechanism operating said dialing mechanism, a

second rack driven by the gramophone motor,

said second rack comprising means for actuating said rack and pinion mechanism, said second rack being coupled with said first rack by a two-armed lever and an articulated link whereby said second rack is driven in the opposite direction to said first rack, and cam and lever mechanism for lowering said sound box onto the sound record,

said cam and lever mechanism being actuated by said second named rack, said mechanism for lowering the sound box onto the record comprising a rotary shaft connected at one end to a crank, said shaft being operated by said second rack and a cam carried by the other end of said shaft .and supporting an arm which in turn supportssaid arm carrying the sound box.

9. The structure of claim '1, said mechanism for returning the sound box to the commencement of the record comprising a lever pivoted at its lower end and movable about its pivot in a vertical plane by link and lever mechanism, said link and lever mechanism being actuated by a link and lever mechanism being actuated by a rack, said rack being driven by the gramophone motor, the upper end of said lever being thereby moved in an arc and carrying-with it said arm supporting said gramophone sound box, said gramophone motor including a toothed annulus,

- means whereby said rack is forced into engagement with said toothed annulus, said means comprising a spring loaded lever upon which said rack is mounted at the moment when'the sound box of the gramophone has completed its travel over the sound record, a cam for releasing said spring loaded lever, a second lever movable by said sound box, and said cam being rotated by said second lever. v

11. The structure of claim 1, cam and lever mechanism, means whereby the movement of the sound box over the sound record actuates said cam and lever mechanism, weight actuated levers releasable by said cam and lever mechanism,

said weight actuated levers comprising means for returning the receiver arm to its depressed positlon and also to open the contact whereby the telephone line is cleared and the device isolated from the telephone system.

' FRANCIS RUPERT DAVIDSON. 

